655973191 has 4 divisors (see below), whose sum is σ = 656488152. Its totient is φ = 655458232.

The previous prime is 655973177. The next prime is 655973251. The reversal of 655973191 is 191379556.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 655973191 - 2¹⁵ = 655940423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (655973291) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 255565 + ... + 258118.

It is an arithmetic number, because the mean of its divisors is an integer number (164122038).

Almost surely, 2^655973191 is an apocalyptic number.

655973191 is a deficient number, since it is larger than the sum of its proper divisors (514961).

655973191 is a wasteful number, since it uses less digits than its factorization.

655973191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 514960.

The product of its digits is 255150, while the sum is 46.

The square root of 655973191 is about 25611.9735865864. The cubic root of 655973191 is about 868.8844604880.

The spelling of 655973191 in words is "six hundred fifty-five million, nine hundred seventy-three thousand, one hundred ninety-one".